90 SC water pump pulley fell off!

SC-HELLSS

Registered User
Drove to work, parked it and seconds later the engine went haywire. Turned it off right away and checked the engine later at lunch. The pulley for the water pump has actually came off the shaft to the water pump and was dangling on the drive belt.

I tapped it back into place, seemed very tight. Drove it home (about 8 miles) and checked under the hood, the pulley had moved forward about .25 inches from where I had it positioned.

Clearly I am missing something in terms of tightening the pulley. There are four bolts on a circular plate on the front of the pulley. Do I tighten these to in turn tighten the pulley onto the shaft? The shaft has no threading of any kind. Either i'm missing some part which holds it in place or these bolts are what need to be tightened.

I know this seems like a silly question but I just don't know the solution myself. Thanks for any help you could provide!
 
Just the four bolts.

I assume you lost the original bolts so you're working with fresh now... add flat or lock washers and a bit of medium loctite. Be sure the pulley hasn't been damaged or tweaked, etc.
 
thanks!

Actually all four bolts/washers are still on the pulley :cool:, they weren't falling out, and actually all four were still tight to where I needed a wrench to loosen them... which made me wonder wether or not that was the issue.
 
Actually all four bolts/washers are still on the pulley

I thought since the pulley was dangling perhaps the bolts took a walk :) I would still consider new ones...

Any reason it should have come loose that you know of - maybe some repairs lately? Has it happened before? What is the condition of the shaft and bolt holes now? How old is that water pump?
 
the water pumps been in it since I bought it november 2007. No repairs recently just a new alternator a few months back.

after taking the bolts out and the pulley off, it looks like the "wheel" on the water pumps shaft the pulley bolts to is what is loose, as that and the pulley all came off together, thus the bolts not being loose.

Still that wheel is very tight on the shaft, having trouble even moving it back to where it should be based on the clean spot on the shaft behind the wheel and the alignment of the other pulleys.
 
Still that wheel is very tight on the shaft, having trouble even moving it back to where it should be based on the clean spot on the shaft behind the wheel and the alignment of the other pulleys.

That 'wheel' is the flange that connects the pulley to the shaft - it's not supposed to come loose. As David said, it's time for a new water pump.
 
No way to press the flange on so it does not move freely huh? Perhaps weld it in place haha.

Any suggestions on a water pump? Should I avoid getting them off ebay or are those a good option?

thank you KMT and david for the support!
 
Did you check to see if the shaft still turns? Not sure it would work out to weld it, but that may depend on who does the work, etc. :) It sounds like it's been on there for some time, so, maybe best to take the hint and retire it.

I did mine earlier this year. Bought Bosch branded from RockAuto.
 
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Did you check to see if the shaft still turns? Not sure it would work out to weld it, but that may depend on who does the work, etc. :) It sounds like it's been on there for some time, so, maybe best to take the hint and retire it..

Good point. It probably took a bit of force to spin the flange off the shaft. Most likely a locked up pump!
 
Has anti-freeze, shaft spins freely, car did not move above normal running temperature when I drove it home from work after putting back on and I had let the car run for about 6 minutes before even driving. Really wish there was a plausible way to just anchor the flange in place as i'm sure the pump is good... but if I have to i'll replace it.
 
I can think of ways to maybe anchor it temporarily, but nothing I'd trust long term

Water pumps aren't that easy to do on these cars, so I can sympathize, I guess.

If you have a shop nearby you can trust to weld it (precautions not to zap any electronics, etc.), maybe you can at least ask their opinion. Problem might be getting a flush surface for the pulley and plate.

What you don't want is for something to really come loose while you're cruising along. I can easily imagine much more damage to deal with beyond just putting on a new pump. You may have already used up all your luck :)

You're not in Vancouver, are you?
 
Live 30 minutes north of seattle. I have a buddy who welds, and my neighbor is pretty mechanically inclined. Might run it by them about a possible weld job, was thinking if that's even an option to weld it from the back of the flange, seems to be some room to get back there.

Trying my best to avoid the dreaded water pump replacement :D
 
Not much room back there...
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Good luck.
 
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Are you really foolish enough to risk damaging or ruining an engine over a inexpensive part and a few hours work? Just play it smart and replace the pump. .
 
It won't be possible to weld that with any hope of holding it holding together for any length of time unless you can fully disassemble the shaft from the pump and proper prepare the surfaces. The consumables cost for welding that (and then having it fail) are more than the cost of a new pump and gasket.

As engine rpm's increase it gets progressively harder to turn the shaft and vibrations on the end are significant.
 
As engine rpm's increase it gets progressively harder to turn the shaft and vibrations on the end are significant.

We had a waterpump shaft let go on a V-8 CJ one time, just as we were passing a large truck on a mountain road - naturally, the rpms were up when things got exciting.

When the body shop got done, you couldn't even tell where the fan went thru the hood...
 
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